How to Get the Exhaust Brake to Work at Low Speed

[MattandLana]

Not wanting to inflame the passions, but am I missing something here? Are you saying that normal compression braking (what used to be called engine braking) won't hold the truck's speed in 2nd or 1st, at the speeds you need? If not, then I see the concern. But if it will hold it, then why does it matter whether EB is engaged or not?

 

[Bill Stockard]

Well.... no... the service brakes are much improved over my 2002, but in these Colorado mountains with multi-mile downhill's and 15,000 pushing me, I really don't want to smell my brakes at the bottom ;-) I'm not talking about interstate roads, those are much easier, but the many 2 lane mountain pass roads are the concern.
I locked down into 1st 2 days ago coming down out of the Colorado Monument and that wasn't too bad, but then I had no EB help either and not much traffic.

Tom

I know what you have experienced. We too have driven and towed the 2-lane mountain roads in CO with 15 and 20-mph switchbacks over the years. Soon after our retirement, we towed our 29' Hitchhiker II fifth wheel behind our '92 CTD D350, automatic transmission, no exhaust brake, 3.54 axle ratio. Descending Grand Mesa was a real "sweaty palms, smelling hot brakes, 10-mph 1st gear experience" on this ROAD Years later driving the same road with a '00 CTD 3500, 6-speed manual transmission, PacBrake, 4.10 axle ratio hauling a Lance slide-in truck camper, was a pleasurable experience. The difference was an exhaust brake, manual transmission, and no heavy fifth wheel "pushing" the truck.

Bill

 

[Bill Stockard]

Well.... no... the service brakes are much improved over my 2002, but in these Colorado mountains with multi-mile downhill's and 15,000 pushing me, I really don't want to smell my brakes at the bottom ;-) I'm not talking about interstate roads, those are much easier, but the many 2 lane mountain pass roads are the concern.
I locked down into 1st 2 days ago coming down out of the Colorado Monument and that wasn't too bad, but then I had no EB help either and not much traffic.

Tom

I know what you have experienced. We too have driven and towed the 2-lane mountain roads in CO with 15 and 20-mph switchbacks over the years. Soon after our retirement, we towed our 29' Hitchhiker II fifth wheel behind our '92 CTD D350, automatic transmission, no exhaust brake, 3.54 axle ratio. Descending Grand Mesa was a real "sweaty palms, smelling hot brakes, 10-mph 1st gear experience" on this ROAD Years later driving the same road with a '00 CTD 3500, 6-speed manual transmission, PacBrake, 4.10 axle ratio hauling a Lance slide-in truck camper, was a pleasurable experience. The difference was an exhaust brake, manual transmission, and no heavy fifth wheel "pushing" the truck.

Bill

 

[AH64ID]

Even with the EGR butterfly valve a diesel doesn't compression brake. While it isn't as big of a deal below 20 as it is at higher speeds I enjoy my exhaust brake all the way to a stop, or tight corner, in steep country.

Do I NEED it, no... But I sure LIKE it.

 

[mwilson]

I find that the ECM shutting my brake off at 20mph or so simply maddening. Having to apply the service brakes at that point is nuts.

On a big rig (which I have driven many of) that is not the case. You can stall it out if you don't touch the clutch to trip the switch. I don't understand the logic unless it is to keep folk from sliding through a stop sign or something. You do that with a big rig and it really accelerates one's learning curve........of course truck drivers don't call a lawyer right off the bat like some of the motoring public do whan they screw up......so I'm sure that affects the programming.

 

[tmcIlwain]

Not wanting to inflame the passions, but am I missing something here? Are you saying that normal compression braking (what used to be called engine braking) won't hold the truck's speed in 2nd or 1st, at the speeds you need? If not, then I see the concern. But if it will hold it, then why does it matter whether EB is engaged or not?

Unfortunately, that is correct that going down some of the 'hills' in CO it's always at least in 2nd, and the speed will be too fast. Sometimes I then brake and down shift to 1st and that does help a lot, but I must watch my RPM to and use brakes to avoid the red line... BUT where is my EB to help out???
I'm used to my 2002 6 speed where my EB could be used all the way down into 1st and even to stall speed.
Tom

 

[Newt]

In my 09, RPM governs when the exhaust brake drops out, not MPH.

Newt

 

[RikDavis]

I just crawled home through a rainstorm on some Tn and KY backroads. This is my first truck with EB and also my first automatic since 1974.
The exhaust brake does seem to drop out below 20 mph but the engine RPM also drops to idle so I assume this is caused by the torque converter unlocking? Anyway it is kind of uncomfortable to suddenly have no exhaust brake and no engine braking at 20 mph when it would still be there with a manual transmission. If I let it coast back to around 30 mph and tap the fuel it seems to start working again. The operation of the EB seemed to be less than consistent
I am only towing a 5000 lb trailer so it does not create a really bad situation but I can understand the concern of those with heavier trailers and long downgrades with 5 and 10 mph switchbacks.
For the most part I like the 68RFE but not so much in this situation

For whatever it is worth I was in Tow Haul and tried both normal and smart E brake. Also tried turning off the skid control

 

[bigblock_doc]

You can't expect the EB to do all the work on slowing down. That's why there is a brake pedal.
What did people do before the EB? Drove more carefully, right. The EB is an added bonus for
slowing down.

 

[grabinov]

You can't expect the EB to do all the work on slowing down. That's why there is a brake pedal.
What did people do before the EB? Drove more carefully, right. The EB is an added bonus for
slowing down.

After 4,000+ miles of hauling with my 33' fifth-wheel in August, I'd have to agree. I have seen the following: The exhaust brake is made for slowing or holding speed, not for stopping. When I use it at highway speeds (holding 65 down the 10 mile Cajon pass in CA, etc.) it is spectacular. It totally changes the driving experience. No more white knuckles. I can ride safely in the truck lane with the big rigs without scaring them or me, and I trust them not to jam on the binders in front of me!

When I use it to try to stop the truck, I am disappointed. As guys say, it's really uncomfortable when it quits (at 20-ish) and you have to stab the brake to keep the tuck from doing what feels like running away. I routinely make a turn with my trailer from downhill at 55+mph to a 90 degree right turn onto another highway - which requires you to come to almost a stop, like 5mph. The brake will hold the truck down to 20, bit it's scary when it goes away.

I feel for the guys who are traveling over a distance downhill in first or second at about 20mph. It's not gonna work I fear.

 

[Cummins12V98]

I just crawled home through a rainstorm on some Tn and KY backroads. This is my first truck with EB and also my first automatic since 1974.
The exhaust brake does seem to drop out below 20 mph but the engine RPM also drops to idle so I assume this is caused by the torque converter unlocking? Anyway it is kind of uncomfortable to suddenly have no exhaust brake and no engine braking at 20 mph when it would still be there with a manual transmission. If I let it coast back to around 30 mph and tap the fuel it seems to start working again. The operation of the EB seemed to be less than consistent
I am only towing a 5000 lb trailer so it does not create a really bad situation but I can understand the concern of those with heavier trailers and long downgrades with 5 and 10 mph switchbacks.
For the most part I like the 68RFE but not so much in this situation

For whatever it is worth I was in Tow Haul and tried both normal and smart E brake. Also tried turning off the skid control

Manually drop into 2nd it will slow you even further.

 

[Swizzle]

Has anyone tried the pacbrake load leash system with the factory EB?

 

[smokemifugotem]

i am very disappointed with the eb function on my '14 tradesman and the way the six speed auto shifts. i expected it all to work much better on a truck that cost this much. i spend a lot of time changing rpm and turning the eb on and off trying to get it to work when i need it to instead of concentrating on driving. it needs a lot of refinement as far as i'm concerned before i'll be happy with my truck. i had a reflash done at 600 miles that was supposed to address both of these problems but i saw no improvement with either.

 

[Hoefler]

i am very disappointed with the eb function on my '14 tradesman and the way the six speed auto shifts. i expected it all to work much better on a truck that cost this much. i spend a lot of time changing rpm and turning the eb on and off trying to get it to work when i need it to instead of concentrating on driving. it needs a lot of refinement as far as i'm concerned before i'll be happy with my truck. i had a reflash done at 600 miles that was supposed to address both of these problems but i saw no improvement with either.

The best thing you can do, is turn it on and leave it on. Learn to drive it that way using the throttle. The computer will learn your driving style and habits. Turning it on and off is the worst thing you can do. Also, turn on the tow/haul regardless of towing or not.

 

[Brocky]

I am with Hoefler I run the EB on manual all the time but only use the tow/haul when towing..Am happy with the way it operates.. I also always ran with the "Jake" master switch on all the time with a big truck, DD series 60.

 

[smokemifugotem]

seems like running eb all the time would hurt milage slowing the truck down when not on the throttle then having to use more throttle to maintain momentum even when the truck would normally be coasting on level ground with the e brake turned off.

 

[Brocky]

It is all in your right toes!!! Just like driving on ice,, easy into and off from the throttle.. Learning how to back off enough to let it coast with out put the engine into breaking mode!!!

 

[smokemifugotem]

i'll give that a try. thank you.